Exercise mediated increase in muscular
blood flow is mediated by which
sympathetic fibers
a) Adrenergic
b) Noradrenergic
c) Dopaminergic
d) Cholinergic
Correct Answer - D
Ans. D. Cholinergic
An exercise is a form of stress, and like most stresses, is
accompanied by sympathetic overactivity.
Skeletal muscles have both sympathetic noradrenergic
vasoconstrictor fibers and sympathetic cholinergic vasodilator fibers.
Vasoconstrictor nerve fibers act mainly on veins.
Venoconstriction improves venous return and helps in improving
cardiac output.
On the other hand, sympathetic cholinergic fibers, which are unique
to skeletal muscles, bring about arteriolar dilatation and thereby
increase muscle blood flow.